The present invention relates to a cooling method for a rack-mount server system in which a plurality of computers are stacked. More particularly, the present invention relates to a technique effectively applied to the liquid cooling system in which a coolant is circulated.
In recent years, the rack-mount system has been the mainstream in the system configuration, storage, and installation of a data processing system such as a server. In the rack-mount system, the devices with specific functions are mounted so that they are stacked on each other in a rack cabinet formed based on a particular standard, and the rack-mount system has the advantages as follows: the devices can be freely selected and arranged, the rack-mount server system is excellent in the flexibility and extensibility of the system configuration, and the space occupied by the system can be reduced.
Particularly, the 19 inch rack cabinet defined in the IEC standard (International Electrical Commission)/EIA standard (The Electrical Industries Association) has been the mainstream of the server system, in which the horizontal width between the posts to mount the devices is defined as 451 mm and the height for mounting the devices is defined as 1U (1 EIA=44.45 mm).
Note that FIG. 15 is a perspective view showing the state where the server modules are mounted in the rack cabinet of the conventional rack-mount server system, which is examined as a background of the present invention by the inventors. In the conventional rack-mount server system, a plurality of server modules are mounted in the rack cabinet 10. The rack cabinet 10 is composed of four posts to be the outer frame and four mount angles 11 on which the server modules are mounted.
The device housing 1 of the server module is attached to the mount angles 11 via metal brackets 8. A main substrate 2 is mounted in the device housing 1, and heat-generating components 3 such as CPU (Central Processing Unit) and LSI (Large Scale Integrated circuit) are mounted on the main substrate 2. A heat radiation fin 4 is attached on each of the heat-generating components 3, and cooling fans 5 are mounted on the upstream side or the downstream side of the radiation fins 4 to deliver the air to the radiation fins 4.
Usually, devices 6 such as magnetic storage devices are mounted on the front face of the server module and connectors 7 to the outside are mounted on the rear face of the server module.
In the configuration described above, the outside air is taken by the cooling fans 5 mounted in the device housing 1 from the front face of the devices through the spaces between the devices 6, and after cooling the heat-generating components 3 by the heat radiation fin 4, the air is exhausted through the spaces between the connectors 7 to the rear face or the side faces of the device.
The conventional rack-mount server system mainly employs the forced air cooling system as described above in which the air is taken from the front face of the device by the cooling fan 5 mounted in the device housing 1 of the server module and the air is exhausted to the rear face or the side faces of the device after cooling the heat-generating components 3. Note that the technique relating to the forced air cooling system for the rack-mount system is disclosed in Japanese Patent Laid-Open No. 2000-261172.